A reflow soldering apparatus solders electronic components on a circuit board while transporting the circuit board on a conveyor through a heating chamber where soldering paste is heated and melted and a cooling chamber where the melted solder is cooled.
The reflow soldering apparatus is installed with a fan and a heater to perform reflow soldering of the electronic components using heated gas. A reflow soldering apparatus of this type generally has multiple preheating chambers and reflow chambers in sequence along the transport line of the conveyor. A fan and a heater are installed in each preheating chamber and reflow chamber. The fan and heater are arranged above and below the conveyor. Gas heated while passing through a heater is guided by a blow guidance means installed in each chamber and blown out from many nozzle holes to heat and melt the soldering paste on the printed circuit board mounted with electronic components on the conveyor.
In this reflow soldering apparatus, the fan has a vertical rotating shaft and is installed in the center of each chamber. The fans are arranged in a straight line along the transport line of the conveyor (see for example Japanese Patent Publication No. 2002-134905).
When the size of the fan is enlarged to increase the fan power, the problem occurs that the total length of the reflow soldering apparatus is increased by an increasing amount of the fan size, since these fans are installed in a straight line along the transport line of the conveyor.
In view of the above problems, the present invention has the object of providing a reflow soldering apparatus capable of employing a blowing means with a larger size without increasing the total length of the apparatus.